This invention relates to a novel arm abduction apparatus for use during shoulder arthroscopy. More specifically, this invention relates to a shoulder flexure and abduction device for use during an arthroscopic diagnosis and/or surgical procedure.
An arthroscope is an instrument that permits an orthopedist to visually examine the interior of a patient's joint. Initially arthroscopy was utilized by orthopedists as an examination tool to visually explore a potentially damaged knee joint. More recently the procedure has been extended to examination of other joints of the body and to use as a tool during surgery. As an example, arthroscopy has been used to diagnose and correct some of the most painful shoulder pathologies seen in orthopedic medicine.
Patients experiencing chronic shoulder complaints of pain, catching, popping, clicking, crepitus or weakness may undergo diagnostic arthroscopic surgery when physical, radiographic and/or arthrographic findings are inconclusive. The most commonly seen pathologies in such patients include glenoid labrum tears, complete or incomplete rotator cuff tears, and complete or incomplete biceps tendon tears. Other problems which can be investigated with shoulder arthroscopy are loose bodies, osteoarthritis, rheumatoid arthritis, and tumoral conditions such as synovial osteoshondromatosis.
Shoulder arthroscopy surgical procedures include the removal of loose bodies, excision of glenoid labrum tears, debridgement of rotator cuff and biceps tendon tears, debridgement and lysing of adhesions in the osteoarthritic shoulder, and synovectomy as well as abrasion arthroscopy and arthroscopy of the subdeltoid bursa.
Over the recent past, arthroscopic techniques have developed to the point that arthroscopy is one of the most common surgical procedures performed by orthopedists. During shoulder arthroscopy, the arthroscope must pass through several layers of fat and muscle and penetrate a thick capsule. Proper orientation is essential for the accurate portal placement that is necessary to avoid injury to the underlying neurovascular structures. Gaining entrance to the joint must be considered one of the most technically demanding aspects of the procedure. Consequently, the initial orientation and reliable maintenance of the operative shoulder with respect to instrumentation and the surgeon are crucial.
In shoulder arthroscopy, a patient is positioned in a lateral decubitus position with the surgical arm connected to a traction or similar device. This traction abducts and extends the arm in order to permit near-total circumferential access to the operative shoulder. A patient is moved to the posterior aspect of an operating table so that the surgeon can easily manoeuvre anterior portal instrumentation. Under usual circumstances fifteen to twenty pounds of traction is required to distract the articular surface from the humeral head of the glenoid.
In the past, traction has been achieved either manually or by securing the operative arm to a fixed point. Manual traction by an assistant is limited due to the assistant's fatigue potential and inability to hold a constant position. Moreover a logistical complication is occasioned by the cumbersomeness created by the assistant's body in close proximity to the operative area.
An option to manual traction is fixed point traction. Fixed point traction comprises tying a cord around a patient's wrist and securing the free end to a fixed point. This procedure alleviates the dependency on an assistant as a means of stabilizing the shoulder. Generally when attaching the operative arm to a fixed point, a patient's operative arm is enclosed in a protective drape comprised of a tubular knit cotton stockinette and a surrounding waterproof latex outer sleeve. A traction band is then placed about the patient's wrist overlying the outer sleeve and a traction cord is secured at the wrist by means of a slipknot and run over a pulley. This technique, although expedient, tends to induce edema in cases where constant traction was prolonged as well as post-operative discomfort in the operative wrist.
The above noted techniques were improved by wrapping the length of an operative forearm in an adhesive material and balancing the forearm over a set of pulleys thus creating a suspension system. Although the provision of a load distributing adhesive wrap and suspension system was an enhancement to fixed point traction, it is possible, particularly in the elderly, to tear skin from a patient's forearm upon removal of the adhesive. Still further, during long operative procedures, the suspension system may exhibit a degree of instability due to manipulation of the operative shoulder. Consequently, the operative forearm must be wrapped tightly to offset unwanted movement during the operative procedure. Tight wrappings, however, may constrict a patient's forearm which may lead to vascular blockage.
Modifications in forearm gripping devices have become available within the past few years which allay the difficulties experienced with the adhesive wrap. In more recent surgical procedures, a forearm engaging sheath has been envisioned. In this device, the sheath is lined with rubber and includes a pair of straps to circumferentially bind the sheath to the forearm. This engaging device, while eliminating the tourniquet characteristics of an adhesive wrap, and tendency to tear a patient's outer layer of skin upon removal does not provide an optimum degree of stability over an extended period of time.
An improvement of the above noted forearm gripping device was obtained by lining the device with a traction pad designed to extend along the length of a patient's forearm and frictionally engage the patient's forearm. Though providing the desired stability, the traction pad compresses tissue in the forearm which may limit circulation and lead to vascular blocking during extended operative procedures.
The difficulties suggested in the proceeding are not intended to be exhaustive but rather are among many which may tend to reduce the effectiveness and physician satisfaction with prior forearm gripping devices during arthroscopic diagnosis and/or surgical procedures. Other noteworthy problems may also exist; however, these presented above should be sufficient to demonstrate that shoulder arthroscopy forearm gripping devices appearing in the past will admit to worthwhile improvement.